use warnings; use strict; use warnings; use PDL; print index('hello world', 'lo w'), "\n"; #### Argument "hello world" isn't numeric in subroutine entry at try.pl line 7. Argument "lo w" isn't numeric in subroutine entry at try.pl line 7. 0 #### PDL includes about a dozen perl modules that form the core of the language, plus additional modules that add further functionality. The perl module "PDL" loads all of the core modules automatically, making their functions available in the current perl namespace. #### Exports "use PDL;" exports a large number of routines into the calling namespace. If you want to avoid namespace pollution, you must instead "use PDL::Lite", and include any additional modules explicitly.